Tornadoes, large hail and winds up to 70 mph are possible until 8 p.m. in an area encompassing northern Colorado and parts of Nebraska and Wyoming, forecasters say.

The severe thunderstorm watch encompasses Weld, Morgan, Logan, Washington, Phillips and Sedgwick counties, according to the National Weather Service in Boulder.

A more serious severe thunderstorm warning, which means severe weather has already been spotted, has been issued for Weld County.

In Colorado, a couple of tornadoes, large hail the size of tennis balls and damaging winds are possible, according to the watch notice.

“A tornado is possible in the Front Range but it is more likely on the Eastern Plains,” said Treste Huse, hydrologist for the NWS. “We could see a severe storm in the Denver metro area.”

Severe weather is more likely east of Interstate 25 and north of Interstate 76, Huse said.

Huse said the Denver could get small hail and wind gusts up to 50 mph. Heavy rain is also possible, she said.

The watch encompasses a population of 1.3 million people, 262 schools and 14 hospitals, the weather service says.